It isn’t each release but there are three distinct “generations” of C++ spanning several decades where the style of idiomatic code fundamentally changed to qualitatively improve expressiveness and safety. You have legacy, modern (starting with C++11), and then whatever C++20 is (postmodern?).

This is happening to many older languages because modern software has more intrinsic complexity and requires more rigor than when those languages were first designed. The languages need to evolve to effectively address those needs or they risk being replaced by languages that do.

I’ve been writing roughly the same type of software for decades. What would have been considered state-of-the-art in the 1990s would be a trivial toy implementation today. The languages have to keep pace with the increasing expectations for software to make it easier to deliver reliably.

As someone that has been using C++ extensively for the last 25 years, each release has felt as an incremental improvement. Yes, there are big chunks in each release that are harder to learn, but usually a team can introduce them at their own pace.

The fact that C++ is a very large and complex language and that makes it unapproachable is undeniable though, but I don't think the new releases make it significantly worse. If anything, I think that a some of the new stuff does ease the on-ramp a bit.

C++ can be written as the optimal industrial language it is. Simple core concepts year after year. Minimal adaptation.

The key thing to understand you are still using C with sugar on top. So you need to understand how the language concepts map to the hardware concepts. So it’s much more relevant to understand pointer arithmetic, the difference between stack and heap allocations and so on, rather what the most recent language standard changes.

You can write the same type of C++ for decades. It’s not going to stop compiling. As long as it compiles on your language standard (C++17 is fine I think unless you miss something specific) you are off to the races. And you can write C++17 for the next two decades if you want.